put https://api.fyno.io/v1///subscriptions/preference
This API enables you to update the channel preference of a user for multiple subscription topics. In the JSON payload, enter the subscription ID as keys to update the channel preference. To update the user preference for all subscription topics at once (global preference), use 'all' instead of the subscription id.
Note: If the channel configuration for a subscription topic is set to 'required', then the user preference for the channel cannot be updated.